Men exposed to high levels of testosterone are more likely to rely on gut reactions than thoughtful reasoning, according to a new study in the journal Psychological Science. The research suggests that men with lower levels of testosterone—a common condition among new fathers and men who purposefully lower libidos—may be more capable of responsible decision making. Meanwhile, testosterone-fueled dudes may be more likely to shoot from the hip—often hitting the wrong mental targets.
“For new dads, it could be that reduced T decreases mental risk taking, which is adaptive for taking care of newborns,” Colin Camerer, a behavioral economist at CalTech and lead author on the study, told Fatherly. “Of course, the testosterone system evolved initially in other animals, so the science won’t be complete until we understand whether similar behaviors are evident in other animals, observed in different human cultures, and so forth.”
Camerer and colleagues asked 243 men to self-administer a topical gel containing either testosterone or a placebo. They then took a Cognitive Reflection Test, an evaluation designed to tease out their ability to suppress intuitive responses. CRT questions included: “A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost?” (Ignore your intuition and check your T—the answer is not .10 cents.)
Although the men who took testosterone retained their ability to solve basic math problems, when it came to the cognitive test their scores began to falter. In fact, men hopped up on T were 20 percent less likely to answer the CRT questions correctly than those who received the placebo, and less likely to work slowly, deliberately, and correctly than their peers.
Camerer and colleagues controlled for age, mood, math skills, treatment expectancy, and 14 other hormones—and the results remained robust. They concluded that their findings “suggest a mechanism underlying testosterone’s diverse effects on humans’ judgments and decision-making.” Namely, that high levels of testosterone may inhibit a man’s ability to mentally check conclusions and override gut instincts.
Testosterone levels fluctuate throughout the course of a man’s lifetime, and even throughout the course of the day. The results of this study suggest that situations known to elevate testosterone—scoring a touchdown, flirting at a bar—could reduce good decision making, while situations known to decrease testosterone (fatherhood) could encourage better judgment. Although some studies have shown that dips in T can lead to depression in dads, perhaps new fathers benefit from the ability to be more thoughtful in the care of an infant. After all, it’s better than having a self-confident, intuitive parenting impulse that could wind up damaging a kid.